Insulation cutting apparatus



April 11, J J LEMBITZ ET'AL INSULATION CUTTING APPARATUS I Filed March 27, 1943 INVENTORS EMB/ 7Z JJL Patente d Apr. 11, 1944 INSULATION CUTTING APPARATUS Joseph J. Lembitz and Samuel M. Martin, Baltimore, Md, assignors to pany, Incorporated, New York, N. Y., a cor.- poration of New York Application March 2'7, 1943, Serial No. 480,874

10 Claims.

This invention relates to insulation cutting apparatus and more particularly to an insulation cutting fixture designed to perform a transverse cutting operation upon rubber jacketed cables.

It is frequently desirable to strip from cable cores a part of the insulation adjacent to the ends of insulated cables in order to join the cable conductor to terminals or to splice lengths of the cables. In order that the stripped end of such a cable may fit accurately into a connector secured thereto, it is desirable to have the insulation severed in such manner that the resulting incision lies in one plane and a straight transverse shoulder is left at the end of the remaining insulation after the severed portion of the insulation has been removed. When the cables are insulated with vulcanized rubber compounds or other tough plastics, it is often diificult to sever the insulation on the ends of the cables so that the entire incision lies in one plane.

t is the object of this invention to provide new and improved insulation cutting apparatus. One insulation cutting apparatus embodying the invention comprises a frame on which a rotatable disc is mounted to be rotated by a pivoted handle attached thereto, which carries a cutting blade secured in a slot thereof. A bushing having an opening of about the same size as the cable and having a gauge member to insure that a predetermined length of insulation is severed from the end of the cable, is secured to and rtated by the rotatable disc. By means of such apparatus, an annular incision may be made in the insulation at a predetermined distance from the end of the cable to facilitate stripping the insulation from the cable core.

Other objects and features of the invention will become apparent from the following detailed description of one embodiment of this invention, when read in conjunction with the accompanying drawing, in which Fig. l is a fragmentary side elevation of a cable insulation cutting apparatus embodying the invention;

Fig. 2 is a fragmentary vertical sectional View thereof taken on line 2--2 of Fig. l, and

Fig. 3 is a side view of a cable showing the annular incision produced in the insulaton by the cutting apparatus.

Referring to Fig. 2 of the drawing, an annular disc it) is rotatably mounted on a flange H of an upright it which may be attached to a work bench or other structure. A bushing l4 rotatably mounted in an aperture E5 in the upright I2 has a bore (6 therein whose diameter is substantially Western Electric Comthe same as that of an insulated cable l8 comprising a core 20 surrounded by an insulating covering l9 made of a vulcanized rubber composi tion or the like, and from which a portion of the covering I9 is to be removed. For different sizes of cables, bushings having corresponding sizes of bores may be provided and each bushing fits into the aperture I5 50 that the same apparatus may be used for cutting the insulation on cables of various sizes.

The bushing 14 is secured against longitudinal movement in the aperture l5 by a flange 2| formed on the bushing l4 and a lug 22 removably attached by a screw 23 to the upright l2. The annular disc III has an L-shaped member 25 attached thereto by screws 25-26. The L.- shaped member has an aperture 28 therein in which a pin 29 is slidably mounted and in which a spring .30 bears against a collar 21 on the pin 29 and resiliently forces the pin into a socket 31 in a semicircular shoulder 32 of the bushing It to secure releasably the disc H) and the bushing for rotation together.

A gauging arm 34 is transversely mounted on a rod 35 which is threaded into a threaded socket 36 in the shoulder. The distance of the gauging arm 34 from the shoulder 32 may be adjusted by screwing the rod 35 into the socket 36 the required distance, a nut 31 threaded on the rod 35 against the shoulder 32 serving to retain therod in its adjusted position.

An arm 33 having a transverse handle 39 thereon is pivotally mounted on a pin 40 fixed in the disc I5. The arm 33 has a vertical slot 41 (Fig. 2) formed therein which is bounded by arms 44 and 45. A cutting disc 4.6 and a U-shaped gauge 48 partially surrounding the disc 46 are secured in the slot M by a screw 49. The screw 49 engages a threaded aperture 55 in the arm 44 and passes through an unthreaded aperture 5i in the arm 45. through a pair of elongated slots 52-52 in arms 53 and 54 of the, U-shaped gauge 48, and through an aperture 55 in the disc 46. The arm has a pair of slots -56 therein, of which only one is shown in full lines in Fig. 1, through which screws 58.-58 pass. The screws 58-53 are screwed into threaded apertures 59.-59 in the arm 54 to adjustably secure the gauge 48 against rotation relative to the arm 45. The cutting disc 46 has a heel 5!) (Fig. 1) formed thereon upon which a rigid bar 6| bears to prevent rotation of disc 46 relative to the arm 38. The bar 6| is secured to the arm 38 by screws 62-.-62.

A circular cutting edge 54 and a radial cutthereof, which bear against the cable l8 when the arm 38 is in the position as shown in dotted lines in Fig. 1 and in full lines in Fig. 2. The arcuate surfaces 6868 bearing on the insulation l9 prevent the point 66 from penetrating beyond the insulation into the cable core and thereby prevent injury to the cable core during the insulation cutting operation. Flat end surfaces 69-69 of the arms 53 and 54 bear against the shoulder 32 when the arm 38 is in the position shown in dotted lines in Fig. 1 and prevent the adjacent arcuate surfaces 68-68 from flattening the insulation I9 during the cutting operation.

A catch 10 is secured to the disc ID by screws ll-ll to receive the arm 38 when the arm is rotated into the position shown in dotted lines in Fig. 1. i

In the operation of this device, with the arm 38 depending from the disc I0, substantially as shown in full lines in Fig. 1, an insulated cable I8 is inserted through the bore IS in the bushing l4 until the end of the cable abuts the gauging arm 34 and is held manually in'that position. The arm 38 is then rotated upon the pin 48 in a clockwise direction as seen in Fig. 1 to the position shown in dotted lines in that figure so that the point 66 on the cutting disc46 penetrates the covering l9 to the depth permitted by the surfaces 68 -68 and 6969 on arms 53 and 54 of the gauge 48. The arm 38 then is in engagement with the catch l0 and further attempted rotation of the arm 38 causes the disc I0 and the bushing I 4 secured thereto to rotate about the cable l8. Rotation of these members causes the cutting disc 46 to be forced through the insulation l9 in a circular path and the radial cutting edge 65 thereon makes a ring-like incision 12 (Fig. 3') in the covering l9. After the ring-like incision 12 has been formed, that portion of the covering I9 between the incision I1 and the end of the cable I 8 can be stripped off.

As has been mentioned previously, the exposed length of the rod 35, which determines the amount of the insulation to be stripped from the cable, may be adjusted as desired. The bushing I4 may be removed from the frame l2 by turning the lug 22 and withdrawing the pin 29 from the socket 3| in the shoulder 32'. If several bushings similar to the bushing l4 but having central openings of different sizes are provided, the fixture may be used to cut the insulation of cables of various sizes corresponding to the sizes of the bores in the bushings. Obviously, the gauge 48 can be loosened in the slot 4! and moved with respect to the arms 44 and 45 to leave a larger or smaller portion of the cutting disc 46 exposed for operation on cables having insulation of difierent thicknesses and to effectively prevent injury to the cable core 20 by the point 66 on the cutting disc 46.

The catch 10 holds the arm 38 against the disc l0 during the entire cutting operation and thus causes the arm and the cutting blade to be rotated in a plane perpendicular to the axis of the cable so that the incision 12 will be in saidplane.

The embodiment disclosed hereinabove is il1us trative of the invention and may be modified without departing from the spirit and scope of the invention, as pointed out in and limited only by the appended claims.

What is claimed is:

1. An insulation cutting apparatus comprising a frame, a member having an opening therein rotatably carried by the frame, and a cutter pivotally mounted with respect to the member and movable with the member to out the insulation on a cable inserted in the opening in the member.

' 2. An insulation cutting apparatus comprising a frame, a member rotatably carried by the frame and having an opening therein, an arm pivotally attached to the rotatable member for movement with respect to the member and for rotating the member around a cable positioned in the opening in the member, a cutting blade secured to the arm to out the insulation of the cable as the arm and the member are rotated around the cable, and a gauge adjustably secured to the arm, whereby a, predetermined portion of the blade may be exposed to cut the insulation of the cable to a predetermined depth.

3. An insulation cutting apparatus comprising a frame having an opening therein through which an insulated cable may be inserted, a gauge adjustably secured with respect to the frame to permit insertion of only a predetermined length of a cable through the opening in the frame, a member rotatably carried by the frame, and cutting means pivotally attached to the rotatable member for movement with respect to the rotatable member and a cable inserted through the opening and for rotating the rotatable member around the cable with the cutting means to sever the insulation on the cable.

4. An insulation cutting apparatus comprising a frame having an opening therein through which an insulated cable may be inserted, a gauge secured adjustably with respect to the frame to permit the insertion of the cable only a predetermined amount through the opening in the frame, a member rotatably borne by the frame, an arm pivotally attached to the member for movement relatively to the member and a cable inserted through the opening in the frame and for rotating the member with respect to the frame and around the cable, a cutting blade secured to the arm to cut the insulation of the cable as the arm and the member are rotated around the cable, and a stop adjustably secured to the arm to bear against the cable during the cutting operation to permit the cutting blade to cut the insulation of the cable to a predetermined depth.

5. An insulation cutting apparatus comprising a frame, a bushing rotatably secured to the frame and having an opening therein through which a cable may be inserted, a member rotatably borne by the frame and. locked to the bushing, an arm pivotally secured to the member to rotate it and the bushing locked thereto relatively to a cable inserted through the opening in the bushing, and a cutting blade secured to the arm for making a ring-like incision in the insulation of the cable as the blade is rotated relatively thereto.

6. An insulation cutting apparatus comprising a frame, a bushing rotatably secured to the frame and having a bore therein through which an insulated cable may be inserted; a gauge secured to the bushing to permit a predetermined length of the cable to be inserted through the bore in the bushing, a member rotatably borne by the frame and secured to the bushing, an arm pivotally secured to the member for movement relative thereto and for rotating the member and the bushing secured thereto in unison relatively to the fixture and around a cable inserted through the bore in the bushing, and a cutting blade secured to the arm for cutting a ring-like incision in the insulation of the cable as the arm and the cutting blade are rotated around the cable.

'7. An insulation cutting apparatus comprising a frame having a circular opening therein, a bushing which is rotatably secured in the cir cular opening and has a bore therein through which an insulated cable may be inserted and which is of substantially the same diameter as the cable whose insulation is to be cut, a gauge secured to the bushing to permit a predetermined length of the cable to be inserted through the opening therein, an annular disc rotatably borne by the frame and secured to the bushing, an arm pivotally secured to the annular disc for movement relative thereto and to rotate the disc and the bushing secured thereto in unison relative to the fixture and around a cable inserted through the bore in the bushing, and a cutting blade secured to the arm to cut a ring-like incision in the insulation of the cable as the arm and the blade are rotated relatively thereto.

8. An insulation cutting apparatus comprising a frame having an aperture therein, a member rotatably mounted on the frame, means pivotally mounted on the member for rotating the member around an insulated cable inserted through the aperture in the frame, and an insulation cutter secured to the pivoted means whereby the cutter may be moved to and away from and around a cable positioned in the aperture to cut the insulation on the cable.

9. An insulation cutting apparatus comprising an upright frame having a circular opening therein and a flange thereon concentric with the opening therein, a removable flanged bushing rotatably secured in the circular opening in the frame, which bushing has a bore therethrough and a semicircular shoulder thereon, a gauge adjustably attached to the shoulder to permit only a predetermined length of an insulated cable to be inserted through the bore of "the bushing, an annular disc rotatably mounted on the flange of the upright frame, means secured to the annular disc for releasably securing the disc to the bushing so that the bushing and the disc may rotate in unison with respect to the upright frame and around a cable inserted through the bore in the bushing, an arm having a slot therein pivotally secured to the disc, 2. disc-like blade removably secured in the slot in the arm having a V-shaped cut out portion in the periphery thereof and a cutting edge formed thereon, and a U-shaped stop adjustably secured in the slot in the arm to expose only a predetermined portion of the disc-like blade.

10. An insulation cutting apparatus comprising an upright frame having a circular opening therein and a flange thereon concentric with the opening therein, a removable bushing rotatably secured in the opening, which bushing has a bore therethrough of substantially the same diameter as an insulated cable to be operated upon and a threaded aperture therein, a gauge adjustably threaded into the aperture in the bushing to permit only a predetermined length of the cable to be inserted through the bore in the bushing, an annular disc rotatably mounted on the flange of the upright frame, means to releasably secure the bushing to the annular disc for movement in unison therewith, an arm pivotally mounted on the annular disc and having a handle thereon and a slot therein, the arm being movable with respect to the disc and to a cable inserted through the bore in the bushing and designed to rotate the annular member and the bushing around the cable, a disc-like blade having a plurality of cutting edges thereon secured in the slot in the arm, and a U-shaped stop adjustably secured in the slot in the arm to expose only a variable predetermined portion of the disc-like blade.

JOSEPH J. LEMBITZ. SAMUEL M. MARTIN. 

